Analysis and research on BDS high-accuracy relative positioning in hydropower projects

To accelerate the replacement and large-scale application of BeiDou navigation satellite system (BDS) terminals and gain an in-depth understanding of the data quality and relative positioning accuracy of the BDS, the data quality and solution accuracy differences between BDS and other satellite navigation systems, as well as among the five frequencies of BDS, were analyzed under the complex observation environment of a pumped storage power station, with a comparison conducted against the side lengths measured by total stations. The results show that: ① BDS outperforms other systems in satellite spatial distribution, multipath resistance and internal accuracy, with the root mean square error of baseline solution lower than that of other systems; ② Optimizing the satellite and frequency selection of BDS can improve the accuracy of baseline solution; ③ The internal conformity of the BDS engineering control network is better than that of the multi-constellation combined system, while its external conformity is slightly inferior to the latter. Based on the research results of this experiment, the standalone BDS can be applied to the survey of high-precision construction control networks in hydropower engineering.